DC voltage superimposed on AC voltage application type bipolar electropolymerization system and synapse device manufacturing method using the same

Abstract

An electropolymerization system is provided. The electropolymerization system comprises a first driving electrode, a second driving electrode spaced apart from the first driving electrode in a first direction, a first positive electrode disposed between the first driving electrode and the second driving electrode, a second positive electrode disposed between the first positive electrode and the second driving electrode, a third positive electrode disposed between the first driving electrode and the second driving electrode such that it does not overlap with the first positive electrode and the second positive electrode in the first direction, and a polymerization solution comprising a monomer, a supporting electrolyte, a sacrificial material that is reduced as the monomer is oxidized, and a solvent, wherein the first driving electrode, the second driving electrode, the first positive electrode, the second positive electrode, and the third positive electrode are disposed within the polymerization solution.

Description

Technology Field

[0001] The present invention relates to a bipolar electropolymerization system and a method for manufacturing a synapse device using the same. Background Technology

[0002] Most organic and inorganic semiconductor materials fabricated using the previously reported non-bipolar electrochemical method are in the form of thin films measuring only a few micrometers, and polymer semiconductors fabricated using the bipolar electrochemical method also mainly exhibit a fiber form measuring a few micrometers.

[0003] Furthermore, in the case of conventionally reported bipolar electrochemical systems, their applications are primarily for electrochemical light-emitting devices and biosensors, and they describe the phenomena themselves that occur when the system is applied, rather than aiming for electrosynthesis or polymerization.

[0004] Furthermore, conventional electropolymerization methods utilizing three-electrode electrochemistry, which serves as the basis for bipolar electrochemical systems, fabricate polymer semiconductors on a working electrode (WE) by using a conductive substrate as the working electrode. Consequently, applying the fabricated polymer semiconductors to electronic devices requires additional post-processing steps, such as a transfer process, which leads to damage to the polymer semiconductors and contact issues.

[0005] Accordingly, the present invention aims to provide an electropolymerization system capable of manufacturing high-quality polymer semiconductors on various non-conductive substrates and producing them over a large area in a short period of time. The problem to be solved

[0006] The technical problem that the present invention aims to solve is to provide a bipolar electropolymerization system and a method for manufacturing a synapse device using the same.

[0007] Another technical problem that the present invention aims to solve is to provide a bipolar electropolymerization system using alternating DC superposition voltage and a method for manufacturing a synapse device using the same.

[0008] Another technical problem that the present invention aims to solve is to provide an electropolymerization system capable of manufacturing high-quality polymer channels on various non-conductive substrates.

[0009] Another technical problem that the present invention aims to solve is to provide an electropolymerization system capable of reducing process unit costs and process time, and a method for manufacturing a synapse device using the same.

[0010] The technical problems that the present invention aims to solve are not limited to those described above. means of solving the problem

[0011] To solve the technical problems described above, the present invention provides an electropolymerization system.

[0012] According to one embodiment, the electropolymerization system comprises a first driving electrode, a second driving electrode spaced apart from the first driving electrode in a first direction, a first anode electrode disposed between the first driving electrode and the second driving electrode, a second anode electrode disposed between the first anode electrode and the second driving electrode, a third anode electrode disposed between the first driving electrode and the second driving electrode but not overlapping with the first anode electrode and the second anode electrode in the first direction, and a polymerization solution comprising a monomer, a supporting electrolyte, a sacrificial material that is reduced as the monomer is oxidized, and a solvent, wherein the first driving electrode, the second driving electrode, the first anode electrode, the second anode electrode, and the third anode electrode are disposed within the polymerization solution.

[0013] According to one embodiment, an electric field is formed between the first and second driving electrodes by a voltage applied to the first and second driving electrodes, and polarization is induced in each of the first to third bipolar electrodes by the electric field, so that the monomer is oxidized at each end of the first to third bipolar electrodes, and the monomer oxidized at each end of the first to third bipolar electrodes is polymerized to form a polymer.

[0014] According to one embodiment, the first and second bipolar electrodes each include a protrusion having the same shape as the first and second bipolar electrodes, and the third bipolar electrode includes a protrusion having a different shape from the protrusions of the first and second bipolar electrodes, wherein first to third polymers are formed at the protrusions of the first to third bipolar electrodes, and the growth rate of the first and second polymers and the growth rate of the third polymer may be different due to the difference in shape between the protrusions of the first and second bipolar electrodes and the protrusion of the third bipolar electrode.

[0015] According to one embodiment, the protrusions of the first and second bipolar electrodes have a triangular shape and the protrusions of the third bipolar electrode have a square shape, and the first and second polymers have a relatively fast growth rate and the third polymer has a relatively slow growth rate.

[0016] According to one embodiment, the protrusion of the first positive electrode and the protrusion of the second positive electrode are arranged to face each other, and the first polymer grows in the direction of the second positive electrode and the second polymer grows in the direction of the first positive electrode.

[0017] According to one embodiment, the first polymer grown in the direction of the second positive electrode and the second polymer grown in the direction of the first positive electrode may be merged to form a polymer film.

[0018] According to one embodiment, when a first electric field is formed from a first driving electrode with a relatively high potential toward a second driving electrode with a relatively low potential, a first polymer is formed at a protrusion of the first bipolar electrode, and when a second electric field is formed from a second driving electrode with a relatively high potential toward a first driving electrode with a relatively low potential, a second polymer is formed at a protrusion of the second bipolar electrode.

[0019] According to one embodiment, the voltage applied to the first and second driving electrodes may include a third type of voltage in which the first type of voltage and the second type of voltage are superimposed.

[0020] According to another embodiment, the electropolymerization system comprises a first driving electrode and a second driving electrode spaced apart from each other in a first direction, a substrate structure disposed between the first driving electrode and the second driving electrode and arranged such that a plurality of cells form rows and columns, and a polymerization solution provided to the first driving electrode, the second driving electrode, and the substrate structure and comprising a monomer for polymer formation, wherein the cell of the substrate structure may include a substrate, a first positive electrode disposed on one side of the substrate, a second positive electrode disposed on the other side of the substrate, and a third positive electrode disposed on the substrate such that it does not overlap with the first positive electrode and the second positive electrode in the first direction.

[0021] According to another embodiment, by applying voltage to the first and second driving electrodes to form an electric field between the first and second driving electrodes, a polymer film may be formed between the first and second bipolar electrodes of the cell.

[0022] According to another embodiment, the polymer film may include any one of PEDOT (Poly(3,4-ethyldioxythiophene)), P3HT (Poly(3-hexylthiophene)), PPy (Polypyrrole), PT (Polythiophene), DPP (Polydiketopyrrolopyrrole), and PNDI (Poly(naphthalene diimide)).

[0023] According to another embodiment, the substrate may comprise any one of glass, quartz, parylene, Ecoflex, PMDS (Polydimethylsiloxane), SEBS (styrene ethylene / butylene), TPU (thermoplastic polyurethane), PET (Poly(ethylene terephthalate), PBT (polybutylene terephthalate), PI (Polyimide), spin-cast starch film, PA (polyamide), PC (polycarbonate), PE (polyethylene), PAR (polyarylate), PTFE (polytetrafluoroethylene), and PPS (polyphenylene sulfide).

[0025] To solve the technical problems described above, the present invention provides a method for manufacturing a synapse device.

[0026] According to one embodiment, the method may include the steps of: arranging first to third bipolar electrodes spaced apart from each other between a first driving electrode and a second driving electrode; providing a polymerization solution comprising a monomer, a supporting electrolyte, a sacrificial material that is reduced as the monomer is oxidized, and a solvent to the first driving electrode, the second driving electrode, the first bipolar electrode, the second bipolar electrode, and the third bipolar electrode; applying a voltage to the first driving electrode and the second driving electrode to form an electric field between the first driving electrode and the second driving electrode, thereby forming a polymer channel between the first bipolar electrode and the second bipolar electrode; and forming a gate insulating film covering the first to third bipolar electrodes.

[0027] According to one embodiment, the step of forming the polymer channel may include forming a first polymer on the first positive electrode by forming a first electric field from the first driving electrode toward the second driving electrode, forming a second polymer on the second positive electrode by forming a second electric field from the second driving electrode toward the first driving electrode, growing the first polymer formed on the first positive electrode toward the second positive electrode, and growing the second polymer formed on the second positive electrode toward the first positive electrode.

[0028] According to one embodiment, the step of forming the gate insulating film may include providing an insulating source on the first to third bipolar electrodes and curing the insulating source provided on the first to third bipolar electrodes. Effects of the invention

[0029] The electropolymerization system of the present invention comprises a first driving electrode and a second driving electrode spaced apart from each other, a first to third bipolar electrode spaced apart from each other between the first driving electrode and the second driving electrode, and a polymerization solution provided to the first to third bipolar electrodes and containing a monomer for polymer formation, wherein a polymer channel can be formed between the first and second bipolar electrodes by applying a voltage to the first and second driving electrodes to form an electric field between the first and second driving electrodes. Accordingly, since a polymer channel can be formed with a simplified process, the process cost for manufacturing a synapse device can be reduced and the process time can be decreased. Brief explanation of the drawing

[0030] FIG. 1 is a side schematic diagram illustrating each component of an electropolymerization system according to an embodiment of the present invention. FIG. 2 is a drawing for explaining the substrate structure of an electropolymerization system according to an embodiment of the present invention. FIG. 3 is a schematic plan view illustrating each component of an electropolymerization system according to an embodiment of the present invention. FIG. 4 is a schematic plan view illustrating each component of an electropolymerization system according to another embodiment of the present invention. FIG. 5 is a diagram illustrating the structural formulas of materials used as supporting electrolytes included in the polymerization solution of an electropolymerization system according to an embodiment of the present invention. FIG. 6 is a flowchart illustrating a method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 7 is a flowchart for specifically explaining step S300 of the method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 8 is a schematic diagram illustrating step S310 of a method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 9 is a schematic diagram illustrating step S320 of a method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 10 is a schematic diagram illustrating step S330 of a method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 11 is a schematic diagram illustrating step S340 of a method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 12 is a schematic diagram illustrating the process of steps S310 and S320 in the method for manufacturing a synapse device according to an embodiment of the present invention. FIG. 13 is a diagram illustrating the oxidation process of a monomer and the reduction process of a sacrificial material in the method of manufacturing a synapse device according to an embodiment of the present invention using structural formulas. FIG. 14 is a diagram illustrating the structural formulas of polymers included in the polymer channel of a synapse device according to an embodiment of the present invention. Figures 15 and 16 are images of a polymer film formed using an electropolymerization system according to Experimental Example 1 of the present invention. FIG. 17 is a diagram illustrating the components for deriving the effective applied voltage value of an electropolymerization system according to Experimental Example 2 of the present invention. FIG. 18 is a schematic diagram illustrating a polymer film prepared using an electropolymerization system according to Experimental Example 3 of the present invention. Figure 19 is an SEM image of a polymer film prepared using an electropolymerization system according to Experimental Example 3 of the present invention. FIG. 20 is a diagram illustrating the AFM analysis results of a polymer film prepared using an electropolymerization system according to Experimental Example 3 of the present invention. FIG. 21 is a diagram illustrating the difference in thickness according to position of a polymer film manufactured using an electropolymerization system according to Experimental Example 3 of the present invention. FIGS. 22 and 23 are drawings illustrating the spectroscopic analysis results of a polymer film according to Experimental Example 4 of the present invention. Figure 24 is an image of the expected molecular arrangement through microstructure analysis of a polymer film according to Experimental Example 4 of the present invention. FIGS. 25 and 26 are drawings illustrating the GIXD analysis results of a polymer film according to Experimental Example 4 of the present invention. FIG. 27 is a diagram illustrating the results of the uniformity evaluation of a polymer film array according to Experimental Example 5 of the present invention. FIG. 28 is a diagram illustrating the operating mechanism, short-term potentiation characteristics, and long-term potentiation characteristics of a synapse device according to Experimental Example 6 of the present invention. FIG. 29 is a diagram illustrating the long-term potentiation / weakening characteristics of a synapse device according to Experimental Example 6 of the present invention. FIG. 30 is a diagram illustrating the α and β values ​​extracted from the long-term potentiation / weakening characteristics of a synapse device according to Experimental Example 6 of the present invention. FIG. 31 is a diagram illustrating the results of the synaptic plasticity evaluation of a synapse device according to Experimental Example 6 of the present invention. FIG. 32 is a conceptual diagram of a simulation according to Experimental Example 7 of the present invention. FIG. 33 is a diagram illustrating the simulation results according to Experimental Example 7 of the present invention. FIG. 34 is a conceptual diagram for implementing a synapse element circuit according to Experimental Example 8 of the present invention. Specific details for implementing the invention

[0031] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. However, the technical concept of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete and to ensure that the concept of the present invention is sufficiently conveyed to those skilled in the art.

[0032] In this specification, when a component is described as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. Additionally, in the drawings, the thicknesses of the films and regions are exaggerated for the effective description of the technical content.

[0033] Additionally, although terms such as first, second, third, etc., have been used to describe various components in the various embodiments of this specification, these components should not be limited by such terms. These terms are used merely to distinguish one component from another. Accordingly, what is referred to as the first component in one embodiment may be referred to as the second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiment. Furthermore, in this specification, "and / or" is used to mean including at least one of the components listed before and after it.

[0034] In the specification, singular expressions include plural expressions unless the context clearly indicates otherwise. Furthermore, terms such as "include" or "have" are intended to specify the existence of the features, numbers, steps, components, or combinations thereof described in the specification, and should not be understood as excluding the existence or addition of one or more other features, numbers, steps, components, or combinations thereof. Additionally, in this specification, "connection" is used to include both indirectly connecting multiple components and directly connecting them.

[0035] Furthermore, in describing the present invention below, if it is determined that a detailed description of related known functions or configurations could unnecessarily obscure the essence of the invention, such detailed description will be omitted.

[0037] FIG. 1 is a side schematic diagram for explaining each component of an electropolymerization system according to an embodiment of the present invention, FIG. 2 is a diagram for explaining a substrate structure of an electropolymerization system according to an embodiment of the present invention, FIG. 3 is a plan schematic diagram for explaining each component of an electropolymerization system according to an embodiment of the present invention, FIG. 4 is a plan schematic diagram for explaining each component of an electropolymerization system according to another embodiment of the present invention, and FIG. 5 is a diagram for explaining the structural formulas of materials used as supporting electrolytes included in the polymerization solution of an electropolymerization system according to an embodiment of the present invention.

[0038] Referring to FIGS. 1 to 3, the electropolymerization system according to the above embodiment may include a first driving electrode (DE1), a second driving electrode (DE2), a substrate structure (ST), and a polymerization solution (PS). Each component is described below.

[0039] The first driving electrode (DE1) and the second driving electrode (DE2) may be spaced apart from each other in a first direction. For example, the first direction may be the X-axis direction shown in FIGS. 1 to 3. According to one embodiment, the first driving electrode (DE1) and the second driving electrode (DE2) may include a metal. For example, the first driving electrode (DE1) and the second driving electrode (DE2) may include platinum (Pt).

[0040] The substrate structure (ST) may be disposed between the first driving electrode (DE1) and the second driving electrode (DE2). According to one embodiment, the substrate structure (ST) may include a first substrate (110), a second substrate (120) disposed on the first substrate (110), a first positive electrode (130), a second positive electrode (140), and a third positive electrode (150) disposed spaced apart from each other on the second substrate (120). More specifically, the first positive electrode (130) may be disposed on one side of the substrate (110) and positioned between the first driving electrode (DE1) and the second driving electrode (DE2). Alternatively, the second positive electrode (140) may be disposed on the other side of the substrate (110) and positioned between the first positive electrode (130) and the second driving electrode (DE2). In contrast, the third positive electrode (150) may be positioned between the first driving electrode (DE1) and the second driving electrode (DE2), but not overlapped with the first positive electrode (130) and the second positive electrode (140) in the first direction (X-axis direction).

[0041] According to one embodiment, the first substrate (110) and the second substrate (120) may comprise a non-conductive material. For example, the first substrate (110) and the second substrate (120) may comprise any one of glass, quartz, parylene, Ecoflex, PMDS (Polydimethylsiloxane), SEBS (styrene ethylene / butylene), TPU (thermoplastic polyurethane), PET (Poly(ethylene terephthalate), PBT (polybutylene terephthalate), PI (Polyimide), spin-cast starch film, PA (polyamide), PC (polycarbonate), PE (polyethylene), PAR (polyarylate), PTFE (polytetrafluoroethylene), and PPS (polyphenylene sulfide).

[0042] According to one embodiment, the first to third bipolar electrodes (130, 140, 150) may each include a lower metal layer and an upper metal layer. The lower metal layer is a layer for adhering the upper metal layer to the second substrate (120) and may include a metal different from the upper metal layer. For example, the lower metal layer may include titanium (Ti) and have a thickness of 3 mm. Alternatively, the upper metal layer may include gold (Au) and have a thickness of 25 mm. That is, the first to third bipolar electrodes (130, 140, 150) may each have a Ti / Au structure.

[0043] According to one embodiment, the first bipolar electrode (130) may include a protrusion (130P) having a triangular shape. The first bipolar electrode (130) may include a first-1 end (130a) and a first-2 end (130b). The first-1 end (130a) may be defined as the end of the first bipolar electrode (130) adjacent to the first driving electrode (DE1). Alternatively, the first-2 end (130b) may be defined as the end facing the first-1 end (130a) and adjacent to the second bipolar electrode (140) among the ends of the first bipolar electrode (130). The protrusion (130P) of the first positive electrode (130) may be formed on the first-2 end (130b), and the first-1 end (130a) may have a flat structure.

[0044] According to one embodiment, the second bipolar electrode (140) may include a protrusion (140P) having a triangular shape. The second bipolar electrode (140) may include a second-1 end (140a) and a second-2 end (140b). The second-1 end (140a) may be defined as the end of the second bipolar electrode (140) adjacent to the second driving electrode (DE2). Alternatively, the second-2 end (140b) may be defined as the end facing the second-1 end (140a) and adjacent to the first bipolar electrode (130) among the ends of the second bipolar electrode (140). The protrusion (140P) of the second bipolar electrode (140) may be formed on the second-2 end (140b), and the second-1 end (140a) may have a flat structure.

[0045] The first positive electrode (130) and the second positive electrode (140) may be arranged such that their respective protrusions (130P, 140P) face each other. That is, the first-2 end (130b) of the first positive electrode (130) and the second-2 end (140b) of the second positive electrode (140) may be arranged such that they face each other.

[0046] According to one embodiment, the third bipolar electrode (150) may include a protrusion (150P) having a square shape. The protrusion (150P) of the third bipolar electrode (150) may be positioned to face the area between the protrusion (130P) of the first bipolar electrode (130) and the protrusion (140P) of the second bipolar electrode (140).

[0047] As described above, due to the difference in the shape of the protrusions of the first anode electrode (130) and the second anode electrode (140) and the shape of the protrusion of the third anode electrode (150), the growth rate of the first polymer and the second polymer formed at the first anode electrode (130) and the second anode electrode (140) and the growth rate of the third polymer formed at the third anode electrode (150) may differ from each other during the electropolymerization process described later.

[0048] More specifically, the first polymer and the second polymer formed at the first anode electrode (130) and the second anode electrode (140), which have a triangular protrusion shape, may have a relatively fast growth rate, whereas the third polymer formed at the third anode electrode (150), which has a square protrusion shape, may have a relatively slow growth rate. Accordingly, a polymer film formed by the first polymer and the second polymer is formed between the first anode electrode (130) and the second anode electrode (140), whereas a polymer film formed by the first polymer and the third polymer and a polymer film formed by the second polymer and the third polymer may not be formed between the first anode electrode (130) and the third anode electrode (150) and between the second anode electrode (130) and the third anode electrode (150). That is, a polymer film is formed between the first positive electrode (130) and the second positive electrode (140), whereas a polymer film may not be formed between the first positive electrode (130) and the third positive electrode (150) and between the second positive electrode (140) and the third positive electrode (150).

[0049] According to another embodiment, as shown in FIG. 4, the substrate structure (ST) comprises a plurality of cells (C1~C 12 ) are arranged to form rows and columns, and each cell (C1~C 12 The cells may include the first substrate (110), the second substrate (120), the first anode electrode (130), the second anode electrode (140), and the third anode electrode (150). In this case, each cell (C1~C) is formed by an electropolymerization process described later. 12 A polymer film can be uniformly formed between the first positive electrode (130) and the second positive electrode (140) that include the above.

[0050] The first driving electrode (DE1), the second driving electrode (DE2), and the substrate structure (ST) may be placed in a polymerization solution (PS). According to one embodiment, the polymerization solution (PS) may include a monomer, a supporting electrolyte, a sacrificial material, and a solvent.

[0051] The above monomer is a material for forming a polymer, and various materials may be used depending on the type of polymer film to be manufactured using the above electropolymerization system. For example, the polymer film to be manufactured using the above electropolymerization system may include any one of PEDOT (Poly(3,4-ethyldioxythiophene)), P3HT (Poly(3-hexylthiophene)), PPy (Polypyrrole), PT (Polythiophene), DPP (Polydiketopyrrolopyrrole), and PNDI (Poly(naphthalene diimide)), and monomers suitable for their polymerization may be used. More specifically, when manufacturing a polymer film containing PEDOT (Poly(3,4-ethyldioxythiophene)), EDOT (3,4-ethylenedioxythiophene) may be used as the monomer.

[0052] The above supporting electrolyte is a material for improving the mobility of the materials constituting the polymerization solution (PS) during the electropolymerization process, and according to one embodiment, it may include any one of TBAClO4 (tetrabutylammonium perchlorate), TBAPF6 (tetrabutylammonium hexafluorophosphate), and TBABF4 (tetrabutylammonium tetrafluoroborate) having the chemical structural formula shown in FIG. 5. In contrast, according to another embodiment, the supporting electrolyte may comprise any one of [EMIM]:[TFSI](1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), Li:TFSI(lithium bis(trifluoromethylsulfonyl)imide), LiClO4(lithium perchlorate), LiPF6(lithium hexafluorophosphate), LiBF4(lithium tetrafluoroforate), TEAClO4(tetraethylammonium perchlorate), TEAPF6(tetraethylammonium hexafluorophosphate), TEABF4(tetraethylammonium tetrafluoroborate), TBACl(tetrabutylammonium chloride), TBABr(tetrabutylammonium bromide), and TBAI(tetrabutylammonium iodide).

[0053] The sacrificial material is a substance that is reduced as the monomer is oxidized during the electropolymerization process to balance the overall charge, and according to one embodiment, may include BQ (p-benzoquinone). The solvent is for dispersing the monomer, the supporting electrolyte, and the sacrificial material, and according to one embodiment, may include ACN (acetonitrile).

[0054] For example, the polymerization solution (PS) can be prepared by stirring EDOT at a concentration of 150 mM, a supporting electrolyte at a concentration of 3 mM (any one of TBAClO4, TBAPF6, and TBABF4), and BQ at a concentration of 15 mM together with ACN.

[0055] The components of the electropolymerization system according to the embodiments of the present invention have been described above. Hereinafter, a method for manufacturing a synapse device using the electropolymerization system according to the embodiments is described.

[0056] FIG. 6 is a flowchart for explaining a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 7 is a flowchart for specifically explaining step S300 of a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 8 is a schematic diagram for explaining step S310 of a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 9 is a schematic diagram for explaining step S320 of a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 10 is a schematic diagram for explaining step S330 of a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 11 is a schematic diagram for explaining step S340 of a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 12 is a schematic diagram for explaining the progress of steps S310 and S320 of a method for manufacturing a synapse device according to an embodiment of the present invention, FIG. 13 is a diagram for explaining the oxidation process of a monomer and the reduction process of a sacrificial substance of a method for manufacturing a synapse device according to an embodiment of the present invention Figure 14 is a drawing for explaining structural formulas, and is a drawing for explaining structural formulas of polymers included in the polymer channel of a synapse device according to an embodiment of the present invention.

[0057] Referring to FIG. 6, the first to third bipolar electrodes (130, 140, 150) are arranged so as to be spaced apart from each other between the first driving electrode (DE1) and the second driving electrode (DE2) (S100), and the polymerization solution (PS) may be provided to the first driving electrode (DE1), the second driving electrode (DE2), the first bipolar electrode (130), the second bipolar electrode (140), and the third bipolar electrode (150) (S200). According to one embodiment, the first bipolar electrode (130) may be used as the source electrode of a synapse device, the second bipolar electrode (140) may be used as the drain electrode of a synapse device, and the third bipolar electrode (150) may be used as the gate electrode of a synapse device.

[0058] Referring to FIGS. 7, 8, and 12, a first electric field (EF1) can be formed from the first driving electrode (DE1), which has a relatively high potential, toward the second driving electrode (DE2), which has a relatively low potential, to form a first polymer (PM1) at the first-second end (130b) of the first bipolar electrode (130) (S310). According to one embodiment, a positive voltage (e.g., a voltage of +50 V) can be applied to the first driving electrode (DE1) and the second driving electrode (DE2) can be used as ground to form the first electric field (EF1) from the first driving electrode (DE1) toward the second driving electrode (DE2).

[0059] More specifically, when the first electric field (EF1) is formed, the cations in the polymerization solution (PS) may move toward the first driving electrode (DE1), while the anions may move toward the second driving electrode (DE2). Accordingly, the first-1 end (130a) of the first positive electrode (130), which is relatively rich in cations, may be polarized with a negative charge, while the first-2 end (130b) of the second positive electrode (130), which is relatively rich in anions, may be polarized with a positive charge. The first-second end (130b), polarized with a positive charge, can oxidize the surrounding monomer (e.g., EDOT) as shown in FIG. 13, and the first-first end (130a), polarized with a negative charge, can reduce the surrounding sacrificial material (e.g., BQ) as shown in FIG. 13. As a result, polymerization of the monomer is initiated, and the first polymer (PM1) can be formed on the first-second end (130b).

[0060] Referring to FIGS. 7, 9, and 12, a second electric field (EF2) can be formed from the second driving electrode (DE2), which has a relatively high potential, toward the first driving electrode (DE1), which has a relatively low potential, thereby forming a second polymer (PM2) at the second-2 end (140b) of the second bipolar electrode (140) (S320). According to one embodiment, a positive voltage (e.g., a voltage of +50 V) is applied to the second driving electrode (DE2), and the first driving electrode (DE1) is used as ground, thereby forming the second electric field (EF2) from the second driving electrode (DE2) toward the first driving electrode (DE1).

[0061] More specifically, when the second electric field (EF2) is formed, the cations in the polymerization solution (PS) may move toward the second driving electrode (DE2), while the anions may move toward the first driving electrode (DE1). Accordingly, the 2-1 end (140a) of the second positive electrode (140), which is relatively rich in cations, may be polarized with a negative charge, whereas the 2-2 end (140b) of the second positive electrode (140), which is relatively rich in anions, may be polarized with a positive charge. The second-2 end (140b), polarized with a positive charge, can oxidize the surrounding monomer (e.g., EDOT) as shown in FIG. 13, and the second-1 end (140a), polarized with a negative charge, can reduce the surrounding sacrificial material (e.g., BQ) as shown in FIG. 13. As a result, polymerization of the monomer is initiated, and the second polymer (PM2) can be formed on the second-2 end (140b).

[0062] Referring to FIG. 7 and FIG. 10, the first electric field (EF1) is formed between the first driving electrode (DE1) and the second driving electrode (DE2) so that the first polymer (PM1) formed on the first bipolar electrode (130) can be grown in the direction of the second bipolar electrode (140) (S330).

[0063] Referring to FIG. 7 and FIG. 11, the second electric field (EF2) is formed between the first driving electrode (DE1) and the second driving electrode (DE2) so that the second polymer (PM2) formed on the second bipolar electrode (140) can be grown in the direction of the first bipolar electrode (130) (S340).

[0064] The first polymer (PM1) grown in the direction of the second positive electrode (140) and the second polymer (PM2) grown in the direction of the first positive electrode (130) can be merged with each other. Accordingly, a polymer film (PF) can be formed. According to one embodiment, the S330 step and the S340 step can be performed alternately and repeatedly.

[0065] That is, after forming the first polymer (PM1) and the second polymer (PM2) on the first bipolar electrode (130) and the second bipolar electrode (140), respectively, through steps S310 and S320, the first polymer (PM1) and the second polymer (PM2) can be grown through the repeated performance of steps S330 and S340. The grown first polymer (PM1) and the second polymer (PM2) can be merged with each other, and the polymer film (PF) can be formed by the merged first polymer (PM1) and the second polymer (PM2). The polymer film (PF) can be defined as a polymer channel. That is, the polymer film can be used as a channel of the synapse device.

[0066] The polymer film (PF) may comprise a material in which the polymer formed by polymerizing the monomer is doped by an anion of the supporting electrolyte. For example, if the monomer comprises EDOT and the supporting electrolyte comprises TBAClO4, the polymer film (PF) may comprise PEDOT:ClO3, in which ClO3 is doped into PEDOT, as shown in FIG. 14. Alternatively, if the monomer comprises EDOT and the supporting electrolyte comprises TBAPF6, the polymer film (PF) may comprise PEDOT:PF6, in which PF6 is doped into PEDOT, as shown in FIG. 14. Alternatively, if the monomer comprises EDOT and the supporting electrolyte comprises TBAABF4, the polymer film (PF) may comprise PEDOT:BF4, in which BF4 is doped into PEDOT, as shown in FIG. 14.

[0067] According to one embodiment, steps S310 and S320 may be defined as seeding steps. Alternatively, steps S330 and S340 may be defined as propagation steps.

[0068] According to one embodiment, the type of voltage applied in the seeding step (S310, S320) and the type of voltage applied in the proliferation step (S330, S340) are controlled differently from each other, thereby improving the uniformity and reliability of the polymer film (PF).

[0069] More specifically, in the seeding step (S310, S320), a first type voltage (AC voltage) is applied, whereas in the multiplication step (S330, S340), a third type voltage (AC-DC superposition voltage) in which the first type voltage (AC voltage) and the second type voltage (DC voltage) are superimposed may be applied. Additionally, the frequency in the seeding step (S310, S320) and the multiplication step (S330, S340) may be maintained at the same level.

[0070] In contrast, if the second type of voltage (DC voltage) or the third type of voltage (AC-DC superposition voltage) is applied in the seeding step (S310, S320), the formation of the first polymer (PM1) and the second polymer (PM2) may not be easily achieved, or even if formed, the reliability of the first polymer (PM1) and the second polymer (PM2) may be low.

[0071] In addition, if the first type of voltage (AC voltage) or the second type of voltage (DC voltage) is applied during the proliferation step (S330, S340), the first polymer (PM1) and the second polymer (PM2) may not grow uniformly, or even if they grow uniformly, the growth rate may be significantly reduced.

[0072] In addition, if the first type of voltage (AC voltage) is applied in both the seeding step (S310, S320) and the proliferation step (S330, S340), a problem may arise in which the growth rate of the first polymer (PM1) and the second polymer (PM2) is reduced; if the second type of voltage (DC voltage) is applied in both the seeding step (S310, S320) and the proliferation step (S330, S340), a problem may arise in which the formation and growth of the first polymer (PM1) and the second polymer (PM2) are not easily achieved; and if the third type of voltage (AC-DC superposition voltage) is applied in both the seeding step (S310, S320) and the proliferation step (S330, S340), a problem may arise in which the uniformity of the polymer film (PF) is reduced, thereby reducing electrical characteristics (e.g., electrical conductivity).

[0073] However, as described above, when the first type of voltage (AC voltage) is applied in the seeding step (S310, S320) and the third type of voltage (AC-DC superposition voltage) is applied in the proliferation step (S330, S340), the formation and growth of the first polymer (PM1) and the second polymer (PM2) can be easily achieved, so the uniformity, reliability, and electrical properties (e.g., electrical conductivity) of the polymer film (PF) can be improved.

[0074] Referring to FIG. 5, after steps S310 to S340, a gate insulating film covering the first to third bipolar electrodes (130, 140, 150) may be formed (S400). Accordingly, the synapse device may be manufactured. According to one embodiment, the step of forming the gate insulating film may include providing an insulating source on the first to third bipolar electrodes (130, 140, 150), and curing the insulating source provided on the first to third bipolar electrodes (130, 140, 150).

[0076] For the above, a method for manufacturing a synapse device using an electropolymerization system according to an embodiment of the present invention has been described. Below, specific experimental examples regarding the electropolymerization system according to an embodiment of the present invention and the method for manufacturing a synapse device using the same are described.

[0077] Experimental Example 1: Confirmation of polymer film formation using an electropolymerization system

[0078] After preparing the electropolymerization system described with reference to FIGS. 1 to 3, a polymer film is formed by the method described with reference to FIGS. 6 to 12, wherein the distance (d) between the first driving electrode (DE1) and the second driving electrode (DE2) ext ) was set to 25 mm, and TBAClO4 was used as the supporting electrolyte.

[0079] Figures 15 and 16 are images of a polymer film formed using an electropolymerization system according to Experimental Example 1 of the present invention.

[0080] Referring to FIG. 15, an optical microscope image of a polymer film (Channel) formed between a first positive electrode (Source BPE) and a second positive electrode (Drain BPE) is shown, and referring to FIG. 16, a Scanning Electron Microscopy (SEM) image of the polymer film formation process between the first positive electrode (BPE) and the second positive electrode (BPE) is shown.

[0081] As can be seen in FIGS. 15 and 16, the first polymer formed at the first positive electrode grows toward the second positive electrode, and the second polymer formed at the second positive electrode grows toward the first positive electrode, and it can be seen that the first polymer and the second polymer are merged to form a polymer film.

[0083] Experimental Example 2: Derivation of the Effective Applied Voltage Value of the Electropolymerization System

[0084] Prepare an electropolymerization system as described with reference to FIGS. 1 to 3, wherein the distance (d) between the first driving electrode (DE1) and the second driving electrode (DE2) ext ) is set to 25 mm, and the width (d) of the first to third bipolar electrodes (130, 140, 150) BPE Each was set to 1.686 mm, and TBAClO4 was used as the supporting electrolyte. The width of the first to third positive electrodes (130, 140, 150) refers to the distance between each end (distance between 130a and 130b, distance between 140a and 140b).

[0085] FIG. 17 is a diagram illustrating the components for deriving the effective applied voltage value of an electropolymerization system according to Experimental Example 2 of the present invention.

[0086] Referring to FIG. 17 (a), a schematic diagram of each component for deriving the effective applied voltage value is shown, and referring to FIG. 17 (b), a diagram explaining the results of measuring the oxidation / reduction levels of reactants through cyclic voltammetry.

[0087] The oxidation level of the monomer EDOT and the reduction level of the sacrificial material BQ used in the electropolymerization system according to the above experimental example are 1.33 V and -0.49 V, respectively. To trigger the oxidation reaction of EDOT, which requires a larger reaction potential, a polarization intensity of 1.33 V or higher must be applied to the end of the positive electrode (130 or 140). This means that the total polarization intensity applied to a single positive electrode (130 or 140) must be 2.66 V or higher to induce polymer initiation.

[0088] The effective applied voltage value to be applied to the driving electrode (DE1 or DE2) to induce a polarization strength of 2.66 V or higher was derived by assuming the following three conditions. First, it was assumed that the electric field strength in the solution is uniform throughout the solution; second, it was assumed that the potential gradient applied to the polymerization solution (PS) between the first driving electrode (DE1) and the second driving electrode (DE2) is linear; and third, it was assumed that the polarization strength applied to the positive electrode (130 or 140) in the polymerization solution (PS) also exhibits a linear gradient.

[0089] Assuming that the three conditions described above are satisfied, the effective applied voltage value was derived as follows. The magnitude of the electric field (E) applied to the driving electrode (DE1 or DE2) is expressed as the magnitude of the voltage (V) applied per effective length (d) of the electric field. Since the electric field gradient within the polymerization solution (PS) is the same as the electric field gradient within the positive electrode (130 or 140), a proportional equation as shown in <Equation 1> below can be established.

[0090] <Mathematical Formula 1>

[0091]

[0092] (ΔE ext : An effective applied voltage value, ΔV, applied to the first driving electrode or the second driving electrode to induce polymerization of the monomer. BPE: Total polarization intensity applied to the first positive electrode or the second positive electrode to induce polymerization of the monomer, d BPE : Width of the first positive electrode or the second positive electrode, d ext : Distance between the first driving electrode and the second driving electrode)

[0093] When the specifications of the effective factors adopted in the electropolymerization system according to the above experimental example are applied (d ext =25 mm, d BPE =1.686 mm, ΔV BPE =2.66 V), effective applied voltage value (ΔE ext )= 39.4 V. Accordingly, the minimum applied voltage capable of inducing polymerization of the monomer is 39 V, and in the electropolymerization system according to the experimental example above, conditions were adopted in which 35 V was applied during the seeding stage and 40 V was applied during the proliferation stage.

[0095] Experimental Example 3: Verification of polymer film morphology prepared using an electropolymerization system

[0096] After preparing the electropolymerization system described with reference to FIGS. 1 to 3, a polymer film was manufactured by the method described with reference to FIGS. 6 to 12, using TBABF4 as the supporting electrolyte. In addition, during the seeding step, an AC voltage of 35 V (frequency 3 Hz) was applied for 10 seconds, and during the growth step, a voltage superimposed of an AC voltage of 40 V (frequency 3 Hz) and a DC voltage of 1 V was applied for 60 seconds.

[0097] FIG. 18 is a schematic diagram illustrating a polymer film manufactured using an electropolymerization system according to Experimental Example 3 of the present invention, FIG. 19 is an SEM image of a polymer film manufactured using an electropolymerization system according to Experimental Example 3 of the present invention, FIG. 20 is a diagram illustrating the AFM analysis results of a polymer film manufactured using an electropolymerization system according to Experimental Example 3 of the present invention, and FIG. 21 is a diagram illustrating the difference in thickness according to position of a polymer film manufactured using an electropolymerization system according to Experimental Example 3 of the present invention.

[0098] Referring to FIGS. 18 to 21, a polymer film (PF) connecting the first positive electrode (130) and the second positive electrode (140) is formed by maintaining the polymerization stage for only about 10 seconds. However, to ensure complete formation of the polymer film (PF) and to lower the resistance, the polymerization environment was maintained until the thickness of the polymer film (PF) no longer increased. As a result, at the boundary where the first polymer growing from the first positive electrode (130) toward the second positive electrode (140) and the second polymer growing from the second positive electrode (140) toward the first positive electrode (130) meet, the film shows a rising phenomenon. Consequently, it can be seen that the thickness of the boundary area is thicker than other areas (average 200 to 300 μm), with an average thickness of about 1.5 μm.

[0100] Experimental Example 4: Structural Analysis of Polymer Films

[0101] After preparing the electropolymerization system described with reference to FIGS. 1 to 3, a polymer film was manufactured by the method described with reference to FIGS. 6 to 12, wherein a glass substrate was used as the substrate and TBABF4 was used as the supporting electrolyte. In addition, during the seeding step, an AC voltage of 35 V (frequency 3 Hz) was applied for 10 seconds, and during the proliferation step, a voltage superimposed of an AC voltage of 40 V (frequency 3 Hz) and a DC voltage of 1 V was applied for 60 seconds.

[0102] FIGS. 22 and 23 are drawings for explaining the spectroscopic analysis results of a polymer film according to Experimental Example 4 of the present invention, FIG. 24 is an image of the expected molecular arrangement through microstructure analysis of a polymer film according to Experimental Example 4 of the present invention, and FIGS. 25 and 26 are drawings for explaining the GIXD analysis results of a polymer film according to Experimental Example 4 of the present invention.

[0103] Referring to Fig. 22, a qualitative evaluation of the energy levels of the polymer film was performed by analyzing the US-Vis-NIR absorption spectrum of the polymer film according to Experimental Example 4, and the ratio of polarons and bipolarons formed within the polymer film was analyzed. Compared to the neutral state, the amounts of polaron and bipolaron charges generated within the polymer film were 3.0 and 3.9, respectively, indicating that the electropolymerized polymer film is significantly doped.

[0104] Referring to Fig. 23, the degree of doping of the polymer was indirectly inferred by analyzing the vibrational modes exhibited by each chemical bond within the polymer through Raman spectroscopic analysis of the polymer film according to Experimental Example 4. It was confirmed that the undoped portion of the PEDOT polymer has a benzenoid structure exhibiting repeating units of an aromatic conjugated structure, while the doped portion has a quinoid structure exhibiting repeating units of a quinoid form. In other words, the polymer film according to Experimental Example 4 possesses a structure in which quinoid and benzenoid structures are mixed, and it can be seen that the ratio of quinoid to benzenoid structures varies depending on the degree of doping. Furthermore, Raman spectroscopic analysis revealed that the vibration frequency due to the quinoid structure is 1423 cm⁻¹. -1 Peak intensity appears at this position, and the frequency due to the benzenoid structure is 1435 cm⁻¹ -1It can be confirmed that peak intensity appears at the location. In addition, it can be seen that the ratio of the peak area due to the quinoid structure (IQ) to the peak area due to the benzenoid structure (IB), IQ / IB, shows a value of approximately 62%.

[0105] Referring to FIG. 25, a GIXD pattern image according to the measurement direction of the polymer film according to Experimental Example 4 is shown, and referring to FIG. 26, a GIXD pattern line profile of the polymer film according to Experimental Example 4 is shown.

[0106] More specifically, referring to FIGS. 24 to 26, the microstructure of the electropolymerized PEDOT:BF4 polymer film was analyzed via Grazing Incidence X-ray Diffraction (GIXD) analysis. The polymer exhibited crystal intensities corresponding to (100) and (010) in the out-of-plane direction, and crystal intensities corresponding to (100), (200), and (010) in the in-plane direction. Through this, it can be confirmed that the electropolymerized PEDOT:BF4 polymer possesses a bimodal molecular orientation with a slightly more dominant edge-on direction. Furthermore, depending on the direction of the positive electrode (BPE) and the GIXD incident beam, the polymer film was divided into directions parallel to the positive electrode (BPE) ( / / BPEs) and perpendicular to the positive electrode (⊥BPEs), and the precise molecular orientation was analyzed through microstructural analysis. The positions of the peaks appearing according to the direction are similar, and their values ​​are respectively = 0.47 Å-1 (d = 13.4 Å), It was found to be = 0.46 Å⁻¹ (d = 13.7 Å). In addition, when analyzing the distance between the bipolar electrode (BPE) and the lamellae in the vertical and horizontal directions, in the out-of-plane direction = 3.51 Å in the in-plane direction It shows a value of = 3.43 Å, confirming that the interlamellar distance (d(100)) is greater than the interlamellar distance of pure PEDOT polymer but similar to the interlamellar distance of PEDOT polymer doped with low molecular weight molecules. In addition, the electropolymerized polymer exhibits and It can be inferred that the difference arises from the phenomenon where polymer lamellae are densely packed at the ends of the positive electrode (BPE), but polymers grow by spreading out in a fountain shape near the boundary in the middle of the polymer channel. It can be inferred that the fountain-shaped polymers grow by moving away from each other due to the Coulombic repulsion between the ends of the growing polymers, as they possess the charge of radical cations at the growth points when polymer propagation occurs.

[0108] Experimental Example 5: Evaluation of Uniformity of Polymer Film Arrays

[0109] After preparing the electropolymerization system described with reference to FIGS. 1 to 4, a polymer film was manufactured using the method described with reference to FIGS. 6 to 12, using a 3 x 3 array. More specifically, a substrate structure in which 9 cells form a 3 x 3 array was used, and TBABF4 was used as the supporting electrolyte. The uniformity of the 9 electropolymerized PEDOT:BF4 polymer films in the 3 x 3 array was evaluated, and the uniformity of the properties of the electropolymerized polymer films was proven through three evaluation criteria.

[0110] FIG. 27 is a diagram illustrating the results of the uniformity evaluation of a polymer film array according to Experimental Example 5 of the present invention.

[0111] Figure 27 (a) shows the channel area analysis results in an optical microscope image of one PEDOT:BF4 polymer film, Figure 27 (b) shows the heatmap distribution of the area analysis results of nine polymer films, Figure 27 (c) shows the analysis results of peaks appearing due to vibrations of the quinoid structure and benzenoid structure in the Raman spectrum of one polymer film, Figure 27 (d) shows the heatmap distribution of the analysis results of the ratio (IQ / IB) of the peak area of ​​the quinoid structure (IQ) and the peak area of ​​the benzenoid structure (IB) of nine polymer films, Figure 27 (e) shows the transport characteristics of one polymer film, and Figure 27 (f) shows the heatmap distribution of the maximum transconductance values ​​extracted from each of the nine polymer films.

[0112] Referring to FIGS. 27 (a) and (b), the image of the polymer film is measured using an optical microscope, and then the area of ​​the polymer film is measured using an analysis tool. The effective area is 75 x 75 μm 2 After setting it to , the area of ​​the polymer film corresponding to the effective area was measured. The length and width of the polymer film were each 50 μm 2 and 30 μm 2 It can be confirmed that... The area of ​​the nine polymer films was measured, and the average was 2735 ± 106 μm 2 You can confirm that the value is displayed.

[0113] Referring to Figures 27 (c) and (d), the ratio of quinoidal to benzenoidal structures of nine polymer films was determined through Raman spectroscopy, and the degree of doping was compared. It can be confirmed that the IQ / IB ratio is 66% ± 1.4% on average, indicating a similar degree of doping.

[0114] Referring to Figures 27 (e) and (f), the formed array was fabricated into an Organic Electrochemical Transistor (OECT), and the transfer characteristics and maximum transconductance were compared. V DS The transport characteristics of the OECT were evaluated at -0.6 V, and it was confirmed that the extracted maximum transconductance of the transport characteristics of the 9 channels (polymer film) showed an average of 491.1 μS ± 47.9 μS.

[0116] Experimental Example 6: Characterization of Synapse Devices

[0117] After preparing the electropolymerization system described with reference to FIGS. 1 to 4, a synapse device was fabricated using the method described with reference to FIGS. 6 to 12, utilizing a 3 x 3 array. More specifically, a substrate structure comprising 9 cells arranged in a 3 x 3 array was used, and TBABF4 was used as the supporting electrolyte. Additionally, PEGDA : [EMIM]:[TFSI] : HOMPP = 8:88:4 (w / w%) was used as an insulating source for forming the gate insulating film, and cured by irradiating with 354 nm UV light. 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM]:[TFSI]), poly(ethylene glycol) diacrylate (PEGDA), 2-hydroxy-2-methylpropiophenone (HOMPP).

[0118] When a pulse was injected into the gate electrode to enable the function of the presynaptic terminal, the postsynaptic current was measured at the second bipolar electrode.

[0119] FIG. 28 is a diagram illustrating the operating mechanism, short-term potentiation characteristics, and long-term potentiation characteristics of a synapse device according to Experimental Example 6 of the present invention.

[0120] Referring to Fig. 28, the most representative characteristics of the synapse were evaluated by measuring short-term potentiation (STP) and long-term potentiation (LTP) characteristics while applying a pulse of 0.5 V to the gate. As can be seen in Fig. 28, it can be confirmed that the short-term potentiation and long-term potentiation characteristics, which are representative characteristics of the synapse, are present.

[0121] FIG. 29 is a diagram illustrating the long-term potentiation / weakening characteristics of a synapse device according to Experimental Example 6 of the present invention.

[0122] Referring to Fig. 29, the results of evaluating long-term potentiation / depression (LTP / D) characteristics are shown when pulses of 0.2, 0.3, and 0.5 V (frequency 10 Hz) are applied to the gate at intervals of 50 ms. As can be seen in Fig. 29, long-term potentiation / depression characteristics are observed.

[0123] FIG. 30 is a diagram illustrating the α and β values ​​extracted from the long-term potentiation / weakening characteristics of a synapse device according to Experimental Example 6 of the present invention.

[0124] Referring to Fig. 30(a), the α value (step size of conductance change) and β value (nonlinearity of conductance change) extracted from long-term reinforcement are shown, and referring to Fig. 30(b), the α value (step size of conductance change) and β value (nonlinearity of conductance change) extracted from long-term weakening are shown. The extracted values ​​were used for artificial neural network simulation learning.

[0125] FIG. 31 is a diagram illustrating the results of the synaptic plasticity evaluation of a synapse device according to Experimental Example 6 of the present invention.

[0126] Referring to Fig. 31, the synaptic plasticity evaluation results show that it is maintained for more than 100 seconds, which is comparable to the plasticity characteristics of actual biological synapses.

[0128] Experiment Example 7: Artificial Neural Network-Based Multilayer Perceptron Simulation

[0129] FIG. 32 is a conceptual diagram of a simulation according to Experimental Example 7 of the present invention, and FIG. 33 is a diagram for explaining the simulation results according to Experimental Example 7 of the present invention.

[0130] Referring to Figures 32 and 33, a multi-layer perceptron simulation training based on an Artificial Neural Network (ANN) was performed using the MNIST dataset based on a crossbar array of m x n matrices. As can be seen in Figures 32 and 33, the training test accuracy was 95.20%, indicating excellent results.

[0132] Experiment Example 8: Implementation of Synaptic Element Circuit

[0133] FIG. 34 is a conceptual diagram for implementing a synapse element circuit according to Experimental Example 8 of the present invention.

[0134] Referring to FIG. 34 (a), a simplified schematic diagram of a neuron configured in an actual living organism (left) and a schematic diagram of a multigate circuit mimicking it (right) are shown, and referring to FIG. 34 (b), the actual fabricated multigate circuit is shown. That is, to implement a biomimetic synapse device circuit, a multigate synapse circuit capable of accommodating multiple stimuli was designed.

[0135] FIGS. 35 to 38 are drawings for explaining the implementation of operant conditioning learning through a synaptic element circuit according to Experimental Example 8 of the present invention.

[0136] Referring to FIG. 35, a conceptual diagram of operant conditioning is shown; referring to FIG. 36, a diagram of the structure of a sequence through operant conditioning learning is shown; referring to FIG. 37, a graph of postsynaptic potential according to voltage pulses applied to the presynaptic terminal of a sequence trained to prefer reward is shown; FIG. 38 shows the results of an unlearned sequence (1, 2, 4) and a sequence (3) showing successful operant conditioning learning according to reward and punishment.

[0137] Unlike Pavlov's dog conditioned reflex method, which was learned through a single stimulus, operant conditioning, which allows for learning through multiple stimuli, was taught. Operant conditioning refers to the process of teaching rats to prefer pressing the red button by providing an electric stimulus when pressing the blue button and food when pressing the red button.

[0138] The learning situation regarding reward and punishment when the red button is pressed and when the blue button is pressed was set up as follows using the same mechanism.

[0139] (1) Is the common gate 0.4 V when the red button is pressed, and 0.3 V when the blue button is pressed?

[0140] (2) For acts of rewarding, a positive voltage is applied to the reward gate, and for acts of punishment, a negative voltage is applied to the reward gate.

[0141] Based on the above settings, the sequence was divided into four types and stimulation was applied, after which the postsynaptic current (IPSC) was measured.

[0142] (1) Sequence 1: Case where there is no reward or punishment when the button is pressed

[0143] (2) Sequence 2: Case where there is no reward when the red button is pressed, but punishment is given when the blue button is pressed

[0144] (3) Sequence 3: Case where a reward is given when the red button is pressed and a punishment is given when the blue button is pressed

[0145] (4) Sequence 4: Same as Sequence 3, but the last stimulus is a punishment given by pressing the blue button.

[0146] As a result of training according to the above sequence, we were able to obtain a result in which the learner prefers pressing the red button by giving a reward for pressing the red button in sequence 3.

[0148] Experimental Example 9: Demonstration of Repeatability / Reproducibility of Electropolymerization Systems

[0149] FIG. 39 is a diagram illustrating the results of demonstrating the repeatability / reproducibility of the electropolymerization system according to Experimental Example 9 of the present invention.

[0150] Organic Electrochemical Transistors (OECTs) were fabricated using three 3 x 3 arrays, and the transfer characteristics and maximum transconductance values ​​of two channels were extracted from one device array. More specifically, an electropolymerization system was prepared with reference to FIGS. 1 to 4, and polymer channels were fabricated using the method described with reference to FIGS. 6 to 12, using three 3 x 3 arrays. More specifically, a substrate structure in which nine cells formed a 3 x 3 array was used, and TBABF4 was used as the supporting electrolyte.

[0151] It can be confirmed that the maximum transconductance value appears near 600 μS and the standard deviation is in the double digits, similar to the average values ​​obtained in Figures 27 (e) and (f). Consequently, it can be seen that the electropolymerization system according to the above experimental example can stably and repeatedly reproduce a polymer semiconductor channel array with uniform performance.

[0153] Although the present invention has been described in detail using preferred embodiments, the scope of the invention is not limited to specific embodiments and should be interpreted by the appended claims. Furthermore, those skilled in the art will understand that many modifications and variations are possible without departing from the scope of the invention. Explanation of the symbols

[0154] DE1, DE2: First driving electrode, second driving electrode ST: Substrate structure PS: Polymerization solution 110: First substrate 120: Second substrate 130: First bipolar electrode 130P: Protrusion of the first bipolar electrode 130a, 130b: 1-1 end, 1-2 end 140: Second bipolar electrode 140P: Protrusion of the second bipolar electrode 140a, 140b: 2-1 end, 2-2 end 150: Third bipolar electrode 150P: Protrusion of the third bipolar electrode

Claims

Claim 1 A first driving electrode; a second driving electrode spaced apart from the first driving electrode in a first direction; a first bipolar electrode disposed between the first driving electrode and the second driving electrode; a second bipolar electrode disposed between the first bipolar electrode and the second driving electrode; a third bipolar electrode disposed between the first driving electrode and the second driving electrode, wherein the third bipolar electrode is disposed such that it does not overlap with the first bipolar electrode and the second bipolar electrode in the first direction; An electropolymerization system comprising a polymerization solution including a monomer, a supporting electrolyte, a sacrificial material that is reduced as the monomer is oxidized, and a solvent, wherein the first driving electrode, the second driving electrode, the first anode electrode, the second anode electrode, and the third anode electrode are disposed within the polymerization solution, wherein the first and second anode electrodes have protrusions of the same shape as each other, and the third anode electrode has a protrusion that has a different shape from the protrusions of the first and second anode electrodes, and wherein the growth rate of the polymer formed at the first and second anode electrodes and the growth rate of the polymer formed at the third anode electrode are different due to the difference in shape between the protrusions of the first and second anode electrodes and the protrusion of the third anode electrode. Claim 2 An electropolymerization system according to claim 1, wherein an electric field is formed between the first and second driving electrodes by a voltage applied to the first and second driving electrodes, polarization is induced in each of the first to third bipolar electrodes by the electric field so that the monomer is oxidized at each end of the first to third bipolar electrodes, and the monomer oxidized at each end of the first to third bipolar electrodes is polymerized to form a polymer. Claim 3 An electropolymerization system according to claim 2, wherein first to third polymers are formed at the protrusions of the first to third positive electrodes, respectively, and the growth rate of the first and second polymers and the growth rate of the third polymer are different due to the shape difference between the protrusions of the first and second positive electrodes and the protrusion of the third positive electrode. Claim 4 An electropolymerization system according to claim 3, wherein the protrusions of the first and second bipolar electrodes have a triangular shape and the protrusions of the third bipolar electrode have a square shape, and the first and second polymers have a relatively fast growth rate and the third polymer has a relatively slow growth rate. Claim 5 An electropolymerization system according to claim 3, wherein the protrusion of the first positive electrode and the protrusion of the second positive electrode are arranged to face each other, and the first polymer grows in the direction of the second positive electrode and the second polymer grows in the direction of the first positive electrode. Claim 6 An electropolymerization system according to claim 5, wherein the first polymer grown in the direction of the second positive electrode and the second polymer grown in the direction of the first positive electrode are merged to form a polymer film. Claim 7 An electropolymerization system according to claim 3, wherein a first polymer is formed at a protrusion of the first bipolar electrode when a first electric field is formed from the first driving electrode having a relatively high potential toward the second driving electrode having a relatively low potential, and a second polymer is formed at a protrusion of the second bipolar electrode when a second electric field is formed from the second driving electrode having a relatively high potential toward the first driving electrode having a relatively low potential. Claim 8 An electropolymerization system according to claim 2, wherein a voltage is applied to the first and second driving electrodes to form and grow first and second polymers on the first and second bipolar electrodes, respectively, wherein an alternating current voltage is applied to the first and second driving electrodes during the seeding step for forming the first and second polymers, whereas an alternating current and direct current superposition voltage is applied to the first and second driving electrodes during the proliferation step for growing the first and second polymers. Claim 9 A first driving electrode and a second driving electrode spaced apart from each other in a first direction; a substrate structure disposed between the first driving electrode and the second driving electrode, wherein a plurality of cells are arranged to form rows and columns; An electropolymerization system comprising a polymerization solution provided on the first driving electrode, the second driving electrode, and the substrate structure, the polymerization solution comprising a monomer for polymer formation, wherein the cell of the substrate structure comprises a substrate, a first positive electrode disposed on one side of the substrate, a second positive electrode disposed on the other side of the substrate, and a third positive electrode disposed on the substrate such that it does not overlap with the first positive electrode and the second positive electrode in the first direction, wherein the first and second positive electrodes each have protrusions of the same shape, and the third positive electrode has a protrusion with a shape different from the protrusions of the first and second positive electrodes, and wherein the growth rate of the polymer formed at the first and second positive electrodes and the growth rate of the polymer formed at the third positive electrode are different due to the difference in shape between the protrusions of the first and second positive electrodes and the protrusion of the third positive electrode. Claim 10 An electropolymerization system according to claim 9, comprising forming a polymer film between the first and second bipolar electrodes of the cell by applying a voltage to the first and second driving electrodes to form an electric field between the first and second driving electrodes. Claim 11 In claim 10, the polymer film is an electropolymerization system comprising any one of PEDOT (Poly(3,4-ethyldioxythiophene)), P3HT (Poly(3-hexylthiophene)), PPy (Polypyrrole), PT (Polythiophene), DPP (Polydiketopyrrolopyrrole), and PNDI (Poly(naphthalene diimide)). Claim 12 In claim 9, the substrate is an electropolymerization system comprising any one of glass, quartz, parylene, Ecoflex, PMDS (Polydimethylsiloxane), SEBS (styrene ethylene / butylene), TPU (thermoplastic polyurethane), PET (Poly(ethylene terephthalate), PBT (polybutylene terephthalate), PI (Polyimide), spin-cast starch film, PA (polyamide), PC (polycarbonate), PE (polyethylene), PAR (polyarylate), PTFE (polytetrafluoroethylene), and PPS (polyphenylene sulfide). Claim 13 A step of arranging first to third bipolar electrodes spaced apart from each other between a first driving electrode and a second driving electrode; a step of providing a polymerization solution comprising a monomer, a supporting electrolyte, a sacrificial substance that is reduced as the monomer is oxidized, and a solvent to the first driving electrode, the second driving electrode, the first bipolar electrode, the second bipolar electrode, and the third bipolar electrode; and a step of forming a polymer channel between the first bipolar electrode and the second bipolar electrode by applying a voltage to the first driving electrode and the second driving electrode to form an electric field between the first driving electrode and the second driving electrode. A method for manufacturing a synapse device comprising the step of forming a gate insulating film covering the first to third bipolar electrodes, wherein the first bipolar electrode and the second bipolar electrode are spaced apart from each other in a first direction, and the third bipolar electrode is arranged so as not to overlap with the first and second bipolar electrodes in the first direction, and the first and second bipolar electrodes include protrusions of the same shape, and the third bipolar electrode includes protrusions of a different shape from the protrusions of the first and second bipolar electrodes, and the growth rate of the polymer formed in the first and second bipolar electrodes and the growth rate of the polymer formed in the third bipolar electrode are different due to the difference in shape between the protrusions of the first and second bipolar electrodes and the protrusions of the third bipolar electrode. Claim 14 A method for manufacturing a synapse device according to claim 13, wherein the step of forming the polymer channel comprises: forming a first polymer on the first bipolar electrode by forming a first electric field from the first driving electrode toward the second driving electrode; forming a second polymer on the second bipolar electrode by forming a second electric field from the second driving electrode toward the first driving electrode; growing the first polymer formed on the first bipolar electrode toward the second bipolar electrode; and growing the second polymer formed on the second bipolar electrode toward the first bipolar electrode. Claim 15 A method for manufacturing a synapse device according to claim 14, wherein the step of forming the gate insulating film comprises: providing an insulating source on the first to third bipolar electrodes; and curing the insulating source provided on the first to third bipolar electrodes.

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